Lighting fixture



May 15, 1923. 1,455,375

- H. C. ADAM LIGHTING FIXTURE Filed Aug. 5O 1920 INVt 'NTOR HARRY (IADAM Patented May 1 5, 1923.

are raves HARRY C. ADAM, OF ST. LOUIS, MISSOURI.

LIGHTING FIXTURE.

Application filed August 30, 1920. Serial No. 406,800.

To all whom it may concern Be it known that I, HARRY C. ADAM, citizen ofthe United States, residing at St. Louis, Missouri, have invented acertain new and useful Improvement in Lighting Fixtures, of which thefollowing is a full, clear, and exact description, such as will enableothers skilled in the art to which it appertainsto make and use thesame;

This invention relates to lighting fixtures, and has for its object toprovide an inexpensive lighting fixture of simple con struction andornamental appearance that will direct the major portion of the hori-Zontal, approximately horizontal, and upwardly-inclined rays from thelight source downwardly into the, useful plane, and will also softlyilluminate the ceiling or space above the fixture.

To this end I have devised a lighting fixture that consists of suitablemetal members with connecting means for attachment to or suspension fromthe ceiling of a room and a light reflecting and diffusing means formedof translucent glass and consisting of a hollow member comprising threeseparate parts integrally connected together, namely, a hyperbolic orbell-shaped upper portion open at its upper end and so disposed withrelation to the filament of the lighting unit of .the fixture that themajor portion of the horizontal and approximately horizontal rays willbe re-directed into the useful plane by the convexed inner surface ofsaid upper portion, a bottom portion arranged horizontally underneaththe lighting unit and an annular band or belt portion of concavo-convexshape imvertical cross section arranged between said upper portion andsaid. bottom portion, and preferably of greater diameter at its widestpart than the lower end of the upper portion of said member. Such alighting fixture is inexpensive to manufacture, due to the fact that themetal parts of same are small and of such design that they can beproduced cheaply and the light reflecting and diffusing means consistsof a one-piece glass bowl open at its upper end, and anotherd'esirablefeature of suchra fixture is that the light reflecting anddiffusing member of same is of such form that all portions of thesurface of same will be of substan tially the same brilliancy whenilluminated, thereby producing a fixture that is of exceptionallyattractive appearance.

The figure of the drawing is a View partly in vertical section andpartly in elevation of a lighting fixture constructed in accordance withmy invention.

Referring to the drawingwhich illustrates the preferred form of theinvention, A designates the light directing and diffusing member of thefixture which is preferably formed of translucent glass and providedwith a bottom portion 1 arranged underneath the light source B of thefixture, an upper portion 2 of substantially hyperbolic form orapproximately bell shape provided with a convexed inner surfacethatdirects the major portion of the horizontal and approximately horizontal'rays which are emitted from the light source downwardly into the usefulplane, and an intermediate portion 3 in the form of an annular belt orband of concavo-convex shape in vertical cross section, integrallyconnected to said bottom portion and upper pottion and being of greaterdiameter than the lower end of said bell-shaped upper portion. Thebottom portion 1 of the diffusing member A may be of any preferredshape,-but it is essential that said bottom portion be joined totheupper portion 2 by a belt or band of concavo-convex shape in verticalcrossvsection,v It is also essential that the upper portion 2 be ofsubstantially hyperbolic form or approximately bell shape and of suchlength that the lower edge of same terminates at or below the horizontalplane in which the filament 0c of the light source lies.

The upper end of the member A is open so that it can be passed upwardlyover the light source, and when said member is in use the opening at theupper end of same is closedby a member C, preferably formed of light-'weight sheet metal and equipped with screws or other suitable devices 3that cooperate with an annular rib or flange 4 at the upper edge of themember A to sustain said member in operative position.

In the form of my invention herein illustrated the member C is connectedto a part D that carriesan electrical receptacle 5 in which the lightingunit is mounted. The

fixture can either be mounted upon or arranged in close proximity to theceiling of a room, or it can be suspended from the ceilin by a chain orother suitable means.

A lighting fixture of the construction above descnibed is exceptionallyeflicient, due

- to the fact that the upper portion 2 of the member .A is so arrangedwith relation to l f-the 'filament of the electric lamp-bulb B '7 thatthe major portion of the horizontal and approximately horizontal raysemitted from the light source will strike the convexed in- 1] ner sideof said portion 2 and be deflected downwardly from same through thebottom portion 1 of the member A. The main portion of the downwardlyinclined, oblique rays from the light source pass directly through thebottom portion of the member A- and through the concavo-convex bandimmediately above said bottom portion, and some of the light passesthrough the upper portion 2 of said member and softly illuminat'es theceiling or space above the fixture. .It will, of course, be understoodthat some of the" rays are absorbed by the member A,

or otherwise lost, but when it is realized that over one-third of allthe rays emitted by the lightsource travel in the paths indicated by thedot and dash lines in the drawingand will be utilized in my fixture toilluminate the space beneath the same, a slight internal loss is of noconsequence. Furthermore, the light reflecting and diffusing member isof such form that the rays from the lighting unit strike the differentportions of said member at such angles that all portions of said memberwill be of practically the same degree of brilliancy, thereby producinga fixture having a luminous member of substantially uniform appearancethroughout its entire area.

In order to intercept and utilize light rays above a point where sameare directed downwardly by the portion 2 of the member A, asubstantially flat reflector E of annular form can be arranged inside ofthe memberA and supported on the neck of the lamp B substantially asshown. This deflector E can be made of any suitable material, preferablymetal, such as aluminum or other non-corrosive material, and it isprovided With a depending part (5 that surrounds the neck or the lamp soas to maintain the reflector vE in proper position.

Having thus described my invention,

what I claim as new and desire to secure by concavo-convex shapeinvertical cross section arranged between said upper and bot tomportions and integrally connected to same. V

HARRY C, ADAM.

